Rosai-Dorfman disease extending to the brain.

Rosai-Dorfman disease (RDD) is a sporadic idiopathic sinus histiocytosis plausibly reactive in nature and well responsive to pharmacological and surgical treatment. Though it can affect almost any organ system, involvement of the nervous system is exceedingly rare. When it does affect the brain, spinal cord, and meninges, it could have profound clinical presentations. Most commonly, RDD manifests with massive cervical lymphadenopathy and signs and symptoms that mimic systemic inflammatory state. We describe a progressive RDD that was unresponsive to therapy that started as a benign salivary gland lesion, spread to the skin, bilateral breasts, and eventually manifested as multifocal meningeal deposits that prompted the patient to seek urgent neurosurgical treatment. Early diagnosis and better understanding of the pathophysiology of RDD is needed to develop disease-specific medications that will halt this disease in its early stages. Thus far, the surgical approach remains the most successful treatment option when disease extends to complex organ systems like the central nervous system.